Conventionally, when an electronic appliance or the like is packed, it is common to place, in a cardboard case, a cushioning material for absorbing impact and vibration from outside during transport and place a product (article to be packed) on the cushioning material such that the to-be-cushioned surface of the product rests on the product placement surface of the cushioning material. As one type of such cushioning materials, there are known those which are constructed by folding a single cardboard sheet into a predetermined shape.
For example, Patent Document 1 identified below discloses, as a cushioning material that is constructed by folding a single cardboard sheet, a cardboard cushioning material in which cuts are formed in part of a cardboard sheet according to the exterior shape of an article to be packed so that, when the sheet is folded such that the cuts fit the exterior shape of the article, an article insertion space is left into which at least part of the article can be inserted. Here, with a remaining part of the cardboard sheet, a hollow cushioning portion is formed so as to adjoin the surface of a cardboard stack opposite the article insertion surface.